The invention concerns an elastic clutch of disk design, particularly suited for a split flywheel for an internal combustion engine. A clutch for this type is known from the German patent disclosure 38 41 639.
The prior clutch features mutually engaging clutch halves between which a helical spring is inserted that is relatively long and extends across a large angular area, i.e., is installed in a curved condition. For that purpose, the one clutch half features for the radial and axial guidance an outer area that is round and adapted to the spring windings. Such a spring arrangement is characterized in that for specific operating conditions there are favorable spring properties achieved, namely when large amplitudes of torsional oscillation are to be absorbed and damped with low spring stiffness. But due to its curved installation, the spring is heavily forced outward in a radial direction during the twisting of the two clutch halves. Despite the lubricant contained in the clutch, this leads to heavy frictional damping in the outer winding area and to an uncontrollable adverse effect on the spring characteristic. Additionally, wear occurs on the bearing surface and on the spring, and the curved spring itself is unfavorably stressed on its radially inner windings. In terms of manufacture, it is expensive to produce a high-precision curved spring.
The problem underlying the invention consists is a clutch of the type discussed above where a spring that can be produced at low cost is arranged in such a manner that it is protected from wear and also favorably stressed, while the known is favorable spring properties are retained.